Have you ever walked through an airport or the lobby of a building and noticed a sudden change in the acoustics? Even in a crowd, you hear your own footsteps as if you’d walked across a microphone. Like the acoustics of Barrier Creek panels, this is something I’ve explored in modern human environments. A friend who goes looking for them with me calls them “vocalizers.”
Once you start looking and listening, you find them all over, outdoor gardens, entrances to skyscrapers. One of the best I’ve found is a dome of focused sound created by the ceiling of Terminal C of the George Bush Intercontinental Airport, near the turn to gates 24–27. It’s like stepping through an invisible veil into a secret space. These are architectural simplicities, a circle or cupola pleasing to the eye, maybe with benches or planters or sculptures. The center is often marked with some small feature, a compass star, an intersection of lines, a mosaic of a circle or globe, or simply a drainpipe if not too fancy.
If you happen to pass over that center, or pause in conversation, the effect is immediate. You’ll hear your own voice reflected back on you with startling and encompassing clarity, louder than any other sound in the vicinity.
A related phenomenon is the “whispering wall” or “whispering gallery.” This is where a curved surface carries the slightest vocalization to another, distant location. Grand Central Station in New York has a famous one. On the lower concourse, just outside of the Oyster Bar, the voice of a person standing in one corner will travel up and over the crowd and land on the ears of a person standing in the opposite corner 30 feet away.
The “vocalizer” is slightly different, perhaps more ubiquitous. These are places that broadcast yourself back to you. I’ve taken to calling them “whispering wells.”
Circular is best, though a semicircle will do. Step into the center and say something or make a hiss. Whatever sound you create, even a clearing of your throat if you don’t want to attract attention, will come back from surrounding walls at exactly the same instant, none of the messy humdrum of baffles and angles, no single echo point any closer or father away than the others.
Tell somebody about it, a stranger walking by. I’ve done this; it generally works once they get past their understandable suspicion. Lead them to the center (many of these are in very public and nonthreatening locations) and when they speak to ask what they should do, they shut their mouth instantly, then say something else like hello or echo and look back at you amazed. Some people become giddy with excitement. Try the front of the Transamerica Pyramid in San Francisco—not the finest example, but an easy one to find. It just takes a few seconds. Step into the middle of one of its outdoor circles. An acoustic bubble envelopes you. You can hear the traffic and noise around you, but if you start singing quietly, which generally draws only mild attention, you are singing back to yourself, audience of one.